Soohyung Lee, "Effect of Online Dating on Assortative Matching: Evidence from South Korea," Journal of Applied Econometrics, Vol. 31, No. 6, 2016, pp. 1120-1139. This paper uses three datasets--a dataset from the online dating service, one of the top three major companies in Korea, Korean marriage records (2002 to 2005), and the 2005 Korean population census. The first dataset is from a confidential data source administered by Mr. Woongjin Lee (Jongro 19-2005, Jongro-gu, Seoul, South Korea, Tel: (country code: 82) 1644-2222). Permission to use this data source should be directed to Mr. Lee. The latter two datasets are the property of the Korea Statistics Office (South Korea) which does not permit open access. However, the data are available for purchase at the KSO website: http://mdss.kostat.go.kr/mdssext/index.jsp?sso=ok The file called "lee_onlinedating.do" is the STATA code used for the empirical analyses. I have included some comments in the code for further explanation. This file is an ASCII file in DOS format. It is zipped in the file sl-program.zip. Unix/Linux users should use "unzip -a". Soohyung Lee Department of Economics University of Maryland LeeS [AT] econ.umd.edu